xref: /freebsd/contrib/llvm-project/clang/lib/AST/Mangle.cpp (revision 2e3507c25e42292b45a5482e116d278f5515d04d)
1 //===--- Mangle.cpp - Mangle C++ Names --------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // Implements generic name mangling support for blocks and Objective-C.
10 //
11 //===----------------------------------------------------------------------===//
12 #include "clang/AST/Attr.h"
13 #include "clang/AST/ASTContext.h"
14 #include "clang/AST/Decl.h"
15 #include "clang/AST/DeclCXX.h"
16 #include "clang/AST/DeclObjC.h"
17 #include "clang/AST/DeclTemplate.h"
18 #include "clang/AST/ExprCXX.h"
19 #include "clang/AST/Mangle.h"
20 #include "clang/AST/VTableBuilder.h"
21 #include "clang/Basic/ABI.h"
22 #include "clang/Basic/SourceManager.h"
23 #include "clang/Basic/TargetInfo.h"
24 #include "llvm/ADT/StringExtras.h"
25 #include "llvm/IR/DataLayout.h"
26 #include "llvm/IR/Mangler.h"
27 #include "llvm/Support/ErrorHandling.h"
28 #include "llvm/Support/Format.h"
29 #include "llvm/Support/raw_ostream.h"
30 
31 using namespace clang;
32 
33 // FIXME: For blocks we currently mimic GCC's mangling scheme, which leaves
34 // much to be desired. Come up with a better mangling scheme.
35 
36 static void mangleFunctionBlock(MangleContext &Context,
37                                 StringRef Outer,
38                                 const BlockDecl *BD,
39                                 raw_ostream &Out) {
40   unsigned discriminator = Context.getBlockId(BD, true);
41   if (discriminator == 0)
42     Out << "__" << Outer << "_block_invoke";
43   else
44     Out << "__" << Outer << "_block_invoke_" << discriminator+1;
45 }
46 
47 void MangleContext::anchor() { }
48 
49 enum CCMangling {
50   CCM_Other,
51   CCM_Fast,
52   CCM_RegCall,
53   CCM_Vector,
54   CCM_Std,
55   CCM_WasmMainArgcArgv
56 };
57 
58 static bool isExternC(const NamedDecl *ND) {
59   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND))
60     return FD->isExternC();
61   if (const VarDecl *VD = dyn_cast<VarDecl>(ND))
62     return VD->isExternC();
63   return false;
64 }
65 
66 static CCMangling getCallingConvMangling(const ASTContext &Context,
67                                          const NamedDecl *ND) {
68   const TargetInfo &TI = Context.getTargetInfo();
69   const llvm::Triple &Triple = TI.getTriple();
70 
71   // On wasm, the argc/argv form of "main" is renamed so that the startup code
72   // can call it with the correct function signature.
73   if (Triple.isWasm())
74     if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND))
75       if (FD->isMain() && FD->getNumParams() == 2)
76         return CCM_WasmMainArgcArgv;
77 
78   if (!Triple.isOSWindows() || !Triple.isX86())
79     return CCM_Other;
80 
81   if (Context.getLangOpts().CPlusPlus && !isExternC(ND) &&
82       TI.getCXXABI() == TargetCXXABI::Microsoft)
83     return CCM_Other;
84 
85   const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND);
86   if (!FD)
87     return CCM_Other;
88   QualType T = FD->getType();
89 
90   const FunctionType *FT = T->castAs<FunctionType>();
91 
92   CallingConv CC = FT->getCallConv();
93   switch (CC) {
94   default:
95     return CCM_Other;
96   case CC_X86FastCall:
97     return CCM_Fast;
98   case CC_X86StdCall:
99     return CCM_Std;
100   case CC_X86VectorCall:
101     return CCM_Vector;
102   }
103 }
104 
105 bool MangleContext::shouldMangleDeclName(const NamedDecl *D) {
106   const ASTContext &ASTContext = getASTContext();
107 
108   CCMangling CC = getCallingConvMangling(ASTContext, D);
109   if (CC != CCM_Other)
110     return true;
111 
112   // If the declaration has an owning module for linkage purposes that needs to
113   // be mangled, we must mangle its name.
114   if (!D->hasExternalFormalLinkage() && D->getOwningModuleForLinkage())
115     return true;
116 
117   // C functions with internal linkage have to be mangled with option
118   // -funique-internal-linkage-names.
119   if (!getASTContext().getLangOpts().CPlusPlus &&
120       isUniqueInternalLinkageDecl(D))
121     return true;
122 
123   // In C, functions with no attributes never need to be mangled. Fastpath them.
124   if (!getASTContext().getLangOpts().CPlusPlus && !D->hasAttrs())
125     return false;
126 
127   // Any decl can be declared with __asm("foo") on it, and this takes precedence
128   // over all other naming in the .o file.
129   if (D->hasAttr<AsmLabelAttr>())
130     return true;
131 
132   // Declarations that don't have identifier names always need to be mangled.
133   if (isa<MSGuidDecl>(D))
134     return true;
135 
136   return shouldMangleCXXName(D);
137 }
138 
139 void MangleContext::mangleName(GlobalDecl GD, raw_ostream &Out) {
140   const ASTContext &ASTContext = getASTContext();
141   const NamedDecl *D = cast<NamedDecl>(GD.getDecl());
142 
143   // Any decl can be declared with __asm("foo") on it, and this takes precedence
144   // over all other naming in the .o file.
145   if (const AsmLabelAttr *ALA = D->getAttr<AsmLabelAttr>()) {
146     // If we have an asm name, then we use it as the mangling.
147 
148     // If the label isn't literal, or if this is an alias for an LLVM intrinsic,
149     // do not add a "\01" prefix.
150     if (!ALA->getIsLiteralLabel() || ALA->getLabel().startswith("llvm.")) {
151       Out << ALA->getLabel();
152       return;
153     }
154 
155     // Adding the prefix can cause problems when one file has a "foo" and
156     // another has a "\01foo". That is known to happen on ELF with the
157     // tricks normally used for producing aliases (PR9177). Fortunately the
158     // llvm mangler on ELF is a nop, so we can just avoid adding the \01
159     // marker.
160     StringRef UserLabelPrefix =
161         getASTContext().getTargetInfo().getUserLabelPrefix();
162 #ifndef NDEBUG
163     char GlobalPrefix =
164         llvm::DataLayout(getASTContext().getTargetInfo().getDataLayoutString())
165             .getGlobalPrefix();
166     assert((UserLabelPrefix.empty() && !GlobalPrefix) ||
167            (UserLabelPrefix.size() == 1 && UserLabelPrefix[0] == GlobalPrefix));
168 #endif
169     if (!UserLabelPrefix.empty())
170       Out << '\01'; // LLVM IR Marker for __asm("foo")
171 
172     Out << ALA->getLabel();
173     return;
174   }
175 
176   if (auto *GD = dyn_cast<MSGuidDecl>(D))
177     return mangleMSGuidDecl(GD, Out);
178 
179   CCMangling CC = getCallingConvMangling(ASTContext, D);
180 
181   if (CC == CCM_WasmMainArgcArgv) {
182     Out << "__main_argc_argv";
183     return;
184   }
185 
186   bool MCXX = shouldMangleCXXName(D);
187   const TargetInfo &TI = Context.getTargetInfo();
188   if (CC == CCM_Other || (MCXX && TI.getCXXABI() == TargetCXXABI::Microsoft)) {
189     if (const ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D))
190       mangleObjCMethodNameAsSourceName(OMD, Out);
191     else
192       mangleCXXName(GD, Out);
193     return;
194   }
195 
196   Out << '\01';
197   if (CC == CCM_Std)
198     Out << '_';
199   else if (CC == CCM_Fast)
200     Out << '@';
201   else if (CC == CCM_RegCall)
202     Out << "__regcall3__";
203 
204   if (!MCXX)
205     Out << D->getIdentifier()->getName();
206   else if (const ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D))
207     mangleObjCMethodNameAsSourceName(OMD, Out);
208   else
209     mangleCXXName(GD, Out);
210 
211   const FunctionDecl *FD = cast<FunctionDecl>(D);
212   const FunctionType *FT = FD->getType()->castAs<FunctionType>();
213   const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FT);
214   if (CC == CCM_Vector)
215     Out << '@';
216   Out << '@';
217   if (!Proto) {
218     Out << '0';
219     return;
220   }
221   assert(!Proto->isVariadic());
222   unsigned ArgWords = 0;
223   if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD))
224     if (!MD->isStatic())
225       ++ArgWords;
226   uint64_t DefaultPtrWidth = TI.getPointerWidth(LangAS::Default);
227   for (const auto &AT : Proto->param_types()) {
228     // If an argument type is incomplete there is no way to get its size to
229     // correctly encode into the mangling scheme.
230     // Follow GCCs behaviour by simply breaking out of the loop.
231     if (AT->isIncompleteType())
232       break;
233     // Size should be aligned to pointer size.
234     ArgWords += llvm::alignTo(ASTContext.getTypeSize(AT), DefaultPtrWidth) /
235                 DefaultPtrWidth;
236   }
237   Out << ((DefaultPtrWidth / 8) * ArgWords);
238 }
239 
240 void MangleContext::mangleMSGuidDecl(const MSGuidDecl *GD, raw_ostream &Out) {
241   // For now, follow the MSVC naming convention for GUID objects on all
242   // targets.
243   MSGuidDecl::Parts P = GD->getParts();
244   Out << llvm::format("_GUID_%08" PRIx32 "_%04" PRIx32 "_%04" PRIx32 "_",
245                       P.Part1, P.Part2, P.Part3);
246   unsigned I = 0;
247   for (uint8_t C : P.Part4And5) {
248     Out << llvm::format("%02" PRIx8, C);
249     if (++I == 2)
250       Out << "_";
251   }
252 }
253 
254 void MangleContext::mangleGlobalBlock(const BlockDecl *BD,
255                                       const NamedDecl *ID,
256                                       raw_ostream &Out) {
257   unsigned discriminator = getBlockId(BD, false);
258   if (ID) {
259     if (shouldMangleDeclName(ID))
260       mangleName(ID, Out);
261     else {
262       Out << ID->getIdentifier()->getName();
263     }
264   }
265   if (discriminator == 0)
266     Out << "_block_invoke";
267   else
268     Out << "_block_invoke_" << discriminator+1;
269 }
270 
271 void MangleContext::mangleCtorBlock(const CXXConstructorDecl *CD,
272                                     CXXCtorType CT, const BlockDecl *BD,
273                                     raw_ostream &ResStream) {
274   SmallString<64> Buffer;
275   llvm::raw_svector_ostream Out(Buffer);
276   mangleName(GlobalDecl(CD, CT), Out);
277   mangleFunctionBlock(*this, Buffer, BD, ResStream);
278 }
279 
280 void MangleContext::mangleDtorBlock(const CXXDestructorDecl *DD,
281                                     CXXDtorType DT, const BlockDecl *BD,
282                                     raw_ostream &ResStream) {
283   SmallString<64> Buffer;
284   llvm::raw_svector_ostream Out(Buffer);
285   mangleName(GlobalDecl(DD, DT), Out);
286   mangleFunctionBlock(*this, Buffer, BD, ResStream);
287 }
288 
289 void MangleContext::mangleBlock(const DeclContext *DC, const BlockDecl *BD,
290                                 raw_ostream &Out) {
291   assert(!isa<CXXConstructorDecl>(DC) && !isa<CXXDestructorDecl>(DC));
292 
293   SmallString<64> Buffer;
294   llvm::raw_svector_ostream Stream(Buffer);
295   if (const ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(DC)) {
296     mangleObjCMethodNameAsSourceName(Method, Stream);
297   } else {
298     assert((isa<NamedDecl>(DC) || isa<BlockDecl>(DC)) &&
299            "expected a NamedDecl or BlockDecl");
300     if (isa<BlockDecl>(DC))
301       for (; DC && isa<BlockDecl>(DC); DC = DC->getParent())
302         (void) getBlockId(cast<BlockDecl>(DC), true);
303     assert((isa<TranslationUnitDecl>(DC) || isa<NamedDecl>(DC)) &&
304            "expected a TranslationUnitDecl or a NamedDecl");
305     if (const auto *CD = dyn_cast<CXXConstructorDecl>(DC))
306       mangleCtorBlock(CD, /*CT*/ Ctor_Complete, BD, Out);
307     else if (const auto *DD = dyn_cast<CXXDestructorDecl>(DC))
308       mangleDtorBlock(DD, /*DT*/ Dtor_Complete, BD, Out);
309     else if (auto ND = dyn_cast<NamedDecl>(DC)) {
310       if (!shouldMangleDeclName(ND) && ND->getIdentifier())
311         Stream << ND->getIdentifier()->getName();
312       else {
313         // FIXME: We were doing a mangleUnqualifiedName() before, but that's
314         // a private member of a class that will soon itself be private to the
315         // Itanium C++ ABI object. What should we do now? Right now, I'm just
316         // calling the mangleName() method on the MangleContext; is there a
317         // better way?
318         mangleName(ND, Stream);
319       }
320     }
321   }
322   mangleFunctionBlock(*this, Buffer, BD, Out);
323 }
324 
325 void MangleContext::mangleObjCMethodName(const ObjCMethodDecl *MD,
326                                          raw_ostream &OS,
327                                          bool includePrefixByte,
328                                          bool includeCategoryNamespace) {
329   if (getASTContext().getLangOpts().ObjCRuntime.isGNUFamily()) {
330     // This is the mangling we've always used on the GNU runtimes, but it
331     // has obvious collisions in the face of underscores within class
332     // names, category names, and selectors; maybe we should improve it.
333 
334     OS << (MD->isClassMethod() ? "_c_" : "_i_")
335        << MD->getClassInterface()->getName() << '_';
336 
337     if (includeCategoryNamespace) {
338       if (auto category = MD->getCategory())
339         OS << category->getName();
340     }
341     OS << '_';
342 
343     auto selector = MD->getSelector();
344     for (unsigned slotIndex = 0,
345                   numArgs = selector.getNumArgs(),
346                   slotEnd = std::max(numArgs, 1U);
347            slotIndex != slotEnd; ++slotIndex) {
348       if (auto name = selector.getIdentifierInfoForSlot(slotIndex))
349         OS << name->getName();
350 
351       // Replace all the positions that would've been ':' with '_'.
352       // That's after each slot except that a unary selector doesn't
353       // end in ':'.
354       if (numArgs)
355         OS << '_';
356     }
357 
358     return;
359   }
360 
361   // \01+[ContainerName(CategoryName) SelectorName]
362   if (includePrefixByte) {
363     OS << '\01';
364   }
365   OS << (MD->isInstanceMethod() ? '-' : '+') << '[';
366   if (const auto *CID = MD->getCategory()) {
367     OS << CID->getClassInterface()->getName();
368     if (includeCategoryNamespace) {
369       OS << '(' << *CID << ')';
370     }
371   } else if (const auto *CD =
372                  dyn_cast<ObjCContainerDecl>(MD->getDeclContext())) {
373     OS << CD->getName();
374   } else {
375     llvm_unreachable("Unexpected ObjC method decl context");
376   }
377   OS << ' ';
378   MD->getSelector().print(OS);
379   OS << ']';
380 }
381 
382 void MangleContext::mangleObjCMethodNameAsSourceName(const ObjCMethodDecl *MD,
383                                                      raw_ostream &Out) {
384   SmallString<64> Name;
385   llvm::raw_svector_ostream OS(Name);
386 
387   mangleObjCMethodName(MD, OS, /*includePrefixByte=*/false,
388                        /*includeCategoryNamespace=*/true);
389   Out << OS.str().size() << OS.str();
390 }
391 
392 class ASTNameGenerator::Implementation {
393   std::unique_ptr<MangleContext> MC;
394   llvm::DataLayout DL;
395 
396 public:
397   explicit Implementation(ASTContext &Ctx)
398       : MC(Ctx.createMangleContext()),
399         DL(Ctx.getTargetInfo().getDataLayoutString()) {}
400 
401   bool writeName(const Decl *D, raw_ostream &OS) {
402     // First apply frontend mangling.
403     SmallString<128> FrontendBuf;
404     llvm::raw_svector_ostream FrontendBufOS(FrontendBuf);
405     if (auto *FD = dyn_cast<FunctionDecl>(D)) {
406       if (FD->isDependentContext())
407         return true;
408       if (writeFuncOrVarName(FD, FrontendBufOS))
409         return true;
410     } else if (auto *VD = dyn_cast<VarDecl>(D)) {
411       if (writeFuncOrVarName(VD, FrontendBufOS))
412         return true;
413     } else if (auto *MD = dyn_cast<ObjCMethodDecl>(D)) {
414       MC->mangleObjCMethodName(MD, OS, /*includePrefixByte=*/false,
415                                /*includeCategoryNamespace=*/true);
416       return false;
417     } else if (auto *ID = dyn_cast<ObjCInterfaceDecl>(D)) {
418       writeObjCClassName(ID, FrontendBufOS);
419     } else {
420       return true;
421     }
422 
423     // Now apply backend mangling.
424     llvm::Mangler::getNameWithPrefix(OS, FrontendBufOS.str(), DL);
425     return false;
426   }
427 
428   std::string getName(const Decl *D) {
429     std::string Name;
430     {
431       llvm::raw_string_ostream OS(Name);
432       writeName(D, OS);
433     }
434     return Name;
435   }
436 
437   enum ObjCKind {
438     ObjCClass,
439     ObjCMetaclass,
440   };
441 
442   static StringRef getClassSymbolPrefix(ObjCKind Kind,
443                                         const ASTContext &Context) {
444     if (Context.getLangOpts().ObjCRuntime.isGNUFamily())
445       return Kind == ObjCMetaclass ? "_OBJC_METACLASS_" : "_OBJC_CLASS_";
446     return Kind == ObjCMetaclass ? "OBJC_METACLASS_$_" : "OBJC_CLASS_$_";
447   }
448 
449   std::vector<std::string> getAllManglings(const ObjCContainerDecl *OCD) {
450     StringRef ClassName;
451     if (const auto *OID = dyn_cast<ObjCInterfaceDecl>(OCD))
452       ClassName = OID->getObjCRuntimeNameAsString();
453     else if (const auto *OID = dyn_cast<ObjCImplementationDecl>(OCD))
454       ClassName = OID->getObjCRuntimeNameAsString();
455 
456     if (ClassName.empty())
457       return {};
458 
459     auto Mangle = [&](ObjCKind Kind, StringRef ClassName) -> std::string {
460       SmallString<40> Mangled;
461       auto Prefix = getClassSymbolPrefix(Kind, OCD->getASTContext());
462       llvm::Mangler::getNameWithPrefix(Mangled, Prefix + ClassName, DL);
463       return std::string(Mangled.str());
464     };
465 
466     return {
467         Mangle(ObjCClass, ClassName),
468         Mangle(ObjCMetaclass, ClassName),
469     };
470   }
471 
472   std::vector<std::string> getAllManglings(const Decl *D) {
473     if (const auto *OCD = dyn_cast<ObjCContainerDecl>(D))
474       return getAllManglings(OCD);
475 
476     if (!(isa<CXXRecordDecl>(D) || isa<CXXMethodDecl>(D)))
477       return {};
478 
479     const NamedDecl *ND = cast<NamedDecl>(D);
480 
481     ASTContext &Ctx = ND->getASTContext();
482     std::unique_ptr<MangleContext> M(Ctx.createMangleContext());
483 
484     std::vector<std::string> Manglings;
485 
486     auto hasDefaultCXXMethodCC = [](ASTContext &C, const CXXMethodDecl *MD) {
487       auto DefaultCC = C.getDefaultCallingConvention(/*IsVariadic=*/false,
488                                                      /*IsCXXMethod=*/true);
489       auto CC = MD->getType()->castAs<FunctionProtoType>()->getCallConv();
490       return CC == DefaultCC;
491     };
492 
493     if (const auto *CD = dyn_cast_or_null<CXXConstructorDecl>(ND)) {
494       Manglings.emplace_back(getMangledStructor(CD, Ctor_Base));
495 
496       if (Ctx.getTargetInfo().getCXXABI().isItaniumFamily())
497         if (!CD->getParent()->isAbstract())
498           Manglings.emplace_back(getMangledStructor(CD, Ctor_Complete));
499 
500       if (Ctx.getTargetInfo().getCXXABI().isMicrosoft())
501         if (CD->hasAttr<DLLExportAttr>() && CD->isDefaultConstructor())
502           if (!(hasDefaultCXXMethodCC(Ctx, CD) && CD->getNumParams() == 0))
503             Manglings.emplace_back(getMangledStructor(CD, Ctor_DefaultClosure));
504     } else if (const auto *DD = dyn_cast_or_null<CXXDestructorDecl>(ND)) {
505       Manglings.emplace_back(getMangledStructor(DD, Dtor_Base));
506       if (Ctx.getTargetInfo().getCXXABI().isItaniumFamily()) {
507         Manglings.emplace_back(getMangledStructor(DD, Dtor_Complete));
508         if (DD->isVirtual())
509           Manglings.emplace_back(getMangledStructor(DD, Dtor_Deleting));
510       }
511     } else if (const auto *MD = dyn_cast_or_null<CXXMethodDecl>(ND)) {
512       Manglings.emplace_back(getName(ND));
513       if (MD->isVirtual())
514         if (const auto *TIV = Ctx.getVTableContext()->getThunkInfo(MD))
515           for (const auto &T : *TIV)
516             Manglings.emplace_back(getMangledThunk(MD, T));
517     }
518 
519     return Manglings;
520   }
521 
522 private:
523   bool writeFuncOrVarName(const NamedDecl *D, raw_ostream &OS) {
524     if (MC->shouldMangleDeclName(D)) {
525       GlobalDecl GD;
526       if (const auto *CtorD = dyn_cast<CXXConstructorDecl>(D))
527         GD = GlobalDecl(CtorD, Ctor_Complete);
528       else if (const auto *DtorD = dyn_cast<CXXDestructorDecl>(D))
529         GD = GlobalDecl(DtorD, Dtor_Complete);
530       else if (D->hasAttr<CUDAGlobalAttr>())
531         GD = GlobalDecl(cast<FunctionDecl>(D));
532       else
533         GD = GlobalDecl(D);
534       MC->mangleName(GD, OS);
535       return false;
536     } else {
537       IdentifierInfo *II = D->getIdentifier();
538       if (!II)
539         return true;
540       OS << II->getName();
541       return false;
542     }
543   }
544 
545   void writeObjCClassName(const ObjCInterfaceDecl *D, raw_ostream &OS) {
546     OS << getClassSymbolPrefix(ObjCClass, D->getASTContext());
547     OS << D->getObjCRuntimeNameAsString();
548   }
549 
550   std::string getMangledStructor(const NamedDecl *ND, unsigned StructorType) {
551     std::string FrontendBuf;
552     llvm::raw_string_ostream FOS(FrontendBuf);
553 
554     GlobalDecl GD;
555     if (const auto *CD = dyn_cast_or_null<CXXConstructorDecl>(ND))
556       GD = GlobalDecl(CD, static_cast<CXXCtorType>(StructorType));
557     else if (const auto *DD = dyn_cast_or_null<CXXDestructorDecl>(ND))
558       GD = GlobalDecl(DD, static_cast<CXXDtorType>(StructorType));
559     MC->mangleName(GD, FOS);
560 
561     std::string BackendBuf;
562     llvm::raw_string_ostream BOS(BackendBuf);
563 
564     llvm::Mangler::getNameWithPrefix(BOS, FOS.str(), DL);
565 
566     return BOS.str();
567   }
568 
569   std::string getMangledThunk(const CXXMethodDecl *MD, const ThunkInfo &T) {
570     std::string FrontendBuf;
571     llvm::raw_string_ostream FOS(FrontendBuf);
572 
573     MC->mangleThunk(MD, T, FOS);
574 
575     std::string BackendBuf;
576     llvm::raw_string_ostream BOS(BackendBuf);
577 
578     llvm::Mangler::getNameWithPrefix(BOS, FOS.str(), DL);
579 
580     return BOS.str();
581   }
582 };
583 
584 ASTNameGenerator::ASTNameGenerator(ASTContext &Ctx)
585     : Impl(std::make_unique<Implementation>(Ctx)) {}
586 
587 ASTNameGenerator::~ASTNameGenerator() {}
588 
589 bool ASTNameGenerator::writeName(const Decl *D, raw_ostream &OS) {
590   return Impl->writeName(D, OS);
591 }
592 
593 std::string ASTNameGenerator::getName(const Decl *D) {
594   return Impl->getName(D);
595 }
596 
597 std::vector<std::string> ASTNameGenerator::getAllManglings(const Decl *D) {
598   return Impl->getAllManglings(D);
599 }
600